What does China Bank's mobile banking mean when it says that the customer has logged in?

The answer is: How to deal with the prompt "Mobile phone number is occupied" when registering personal mobile banking of Bank of China:

On the premise of confirming that the mobile phone number has been used by me, you can use the mobile phone number to send a short message QXSJYH (the initials of "Cancel Mobile Banking" can be capitalized, which means to cancel the use of the mobile phone number in the existing personal mobile banking service of BOC). After you send a short message, 95566 will inform you of the processing result by real-time short message.

Specific description: If a mobile phone number has been used by customer A to open personal mobile banking service of China Bank, but customer B wants to open personal mobile banking service of China Bank for the new holder of the mobile phone number, then customer B uses the mobile phone number to send a short message QXSJYH to 95566. At this time, after Customer A releases the mobile phone number, the new cardholder can open the personal mobile banking service of Bank of China. A Customers can continue to use the personal mobile banking service of Bank of China only after changing the personal mobile banking phone number of Bank of China through the counter of Bank of China.